code: def test_get_hypervolume(self) -> None:
      # W/ empty data.
      exp = get_experiment_with_trial()
      self.assertEqual(
          BestPointMixin._get_hypervolume(exp, Mock()), 0.0
      )
  
file_path: Ax/ax/service/tests/test_best_point.py
imports: from unittest.mock import Mock
  import pandas
  from ax.core.arm import Arm
  from ax.core.batch_trial import BatchTrial
  from ax.core.data import Data
  from ax.core.generator_run import GeneratorRun
  from ax.core.optimization_config import MultiObjectiveOptimizationConfig
  from ax.core.trial import Trial
  from ax.exceptions.core import DataRequiredError
  from ax.service.utils.best_point_mixin import BestPointMixin
  from ax.utils.common.testutils import TestCase
  from ax.utils.common.typeutils import checked_cast, not_none
  from ax.utils.testing.core_stubs import get_arm_weights2, get_arms_from_dict, get_experiment_with_batch_trial, get_experiment_with_observations, get_experiment_with_trial
label_desc: Use image node_id 2 for calling the TestBestPointMixin obj's underlying member method code with example usage: obj.test_get_hypervolume() without return types